


The Hunt

by armethaumaturgy



Category: Undertale (Video Game)
Genre: Cross (X-tale) - Freeform, Dust (Dusttale) - Freeform, Ecto-Genitalia, Explicit Sexual Content, Feral Behavior, Horror (Horrortale) - Freeform, Killer (Killertale) - Freeform, Knotting, M/M, Marking, Mating Cycles/In Heat, Multiple Orgasms, Nesting, Nightmare (Dreamtale) - Freeform, Orgasm Delay/Denial, Overstimulation, Possessive Behavior, Praise Kink, Subtle Manipulation, Vaginal Sex, Weapons Kink, bad sans poly - Freeform, cumflation
Language: English
Status: In-Progress
Published: 2021-03-13
Updated: 2021-03-16
Packaged: 2021-03-21 00:48:11
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 7,269
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/30013542
Author URL: https://archiveofourown.org/users/armethaumaturgy/pseuds/armethaumaturgy
Summary: “Horror made a blaster today,” Dust said, around a mouthful of toast. Killer perked up.“Is that so?” Nightmare mused, and Cross couldn’t figure out why he sounded contemplative. Wasn’t that a good thing? That Horror’s magic was recovering enough for him to create blasters again?“Huh-what?” he slurred, much to Nightmare’s amusement.“The Hunt is on,” Nightmare said, and Cross’ mind finally pieced it all together.
Relationships: Sans/Sans (Undertale)
Comments: 20
Kudos: 290





	1. The King's abidance

**Author's Note:**

  * For [Elsword](https://archiveofourown.org/users/Elsword/gifts).

**Notes for the Chapter:**

> edit 17/3/21; i would like to share the WONDERFUL fanart of nightmare from this chapter that [Poppikel](https://twitter.com/poppikel/) on twitter made! im in love with it! please check it out [here!!](https://twitter.com/poppikel/status/1370755018073141252?s=20)

Cross poured himself what had to be his third cup of coffee. His sockets refused to stay open, dipping down despite the fact that the clock was almost to nine AM.

He was looking forward to getting to bed, at which point he’d regret all the coffee, but Horror wouldn’t like it if he fell asleep without breakfast. Or dinner, technically, considering they’d been out on a ‘shopping trip,’ all night.

“Horror made a blaster today,” Dust said, around a mouthful of toast. Killer perked up.

“Is that so?” Nightmare mused, and Cross couldn’t figure out why he sounded contemplative. Wasn’t that a good thing? That Horror’s magic was recovering enough for him to create blasters again?

“Oh, this time’s gonna be fun,” Killer leered, looking entirely too smug. Cross was reminded of the Cheshire cat. 

“Huh-what?” he slurred, much to Nightmare’s amusement.

His piercing eyelight landed on him, and he smiled, though the proper definition would also have to be a ‘leer.’ “The Hunt is on,” he said, and Cross’ mind finally pieced it all together.

A rush of excitement filled him in lieu of the fatigue. He wasn’t sure he’d be able to sleep now.

“I give it ‘til noon,” Dust said, as Horror came back with another plate of sandwiches.

There was magic sparking along his joints, faint but definitely there when one looked close enough. 

Oh, it would be fun, indeed.

* * *

The clock had barely struck noon when Nightmare had felt all his boys scattering around the castle and its forest.

The hallways would’ve been quiet, like the premonition of a storm to come, if not for the muffled scrambling and moving of things coming from Horror’s room down the hallway. Nightmare’s feet made no sound as he walked towards it, like a lamb to the slaughter.

He was more than sure he had already been noticed, but he still paused at the door, listening in for Horror to finish his preparations. All he could feel from beyond the door was longing, and hunger enough to make him worry in any other circumstance.

And yet he waited, until the sounds of fabric rustling died down, and he could make out soft panting.

He raised a hand and knocked on the wood.

“It’s me,” he said, perhaps louder than he needed to. “Your king.”

A few seconds and the door flew open, Horror’s large frame filling the doorway. The look in his eye was primal; there was a flush of crimson all over his skull, and he smelled of pinewood, of blood and fire.

Nightmare’s tentacles lowered, almost dragging across the floor, and he stood tall in turn, reaching out to Horror and cupping his cheekbone in one hand, past the dangerous crackle of magic surrounding him.

“Horror,” he said, infinitely softer than before, as his thumb rubbed over the flushed bone. “I’ve come to you.”

Horror leaned into the touch, eye dilating as he stared down at his boss, his  _ king, _ who had come to him  _ on his own. _ A purr kicked up in the depths of his ribcage, loud and rumbling, and Nightmare just smiled wider, his socket narrowed in amusement.

“Of course I’ve come,” he cooed, like he could read Horror’s thoughts on his face, like he was shouting them at the top of his non-existent lungs, “All the others are fools, to run. They should know by now just how good of a care they’re in, with you. Isn’t that right?”

Nightmare’s hand reached up, to graze the tips of his phalanges over the jagged edges of Horror’s old wound. He had to lean up onto his tiptoes to reach, but Horror’s look was more than worth it, a mix between dazed and determined.

Nightmare leaned in, pressing himself against Horror’s chest as he trailed his claw down the side of Horror’s skull and neck. The shiver it earned him was delightful.

“You’ll show me, won’t you? What they’re missing out on.”

Usually, such blatant coercion wouldn’t go over well with the bigger skeleton, but as he was now, he simply groaned, jaw opening, as if he wanted to devour Nightmare in a single bite. All things considered, he could probably do it. His hands came to Nightmare’s shoulders, drawing his frame close as they pulled him into the room.

_ “In,”  _ Horror ground out, voice so deep it barely sounded like a word, and Nightmare suppressed a smile at how far gone the other skeleton was already.

With the right words, he could have him doing whatever he wished. But no matter how depraved and  _ vile  _ the rest of the multiverse would believe him to be, he did not take advantage of his boys when they were vulnerable. When they were lucid and aware of his intentions? Sure. But never when they couldn’t tell him a clear ‘no.’

He let himself be pulled towards the corner. Horror’s room was a mess — and so must’ve been all the other ones, from his pillaging — but the corner between the wall and the bed was covered in any and all blankets and pillows Horror could find, arranged together into a nest large enough to fit all of his charges.

Nightmare appreciated the softness of the pile as he was all but thrown onto it. He landed on one of Cross’ jackets and he couldn’t help but smile. The entire thing was lined with their clothes, spread carefully around so the nest would keep its shape.

Nightmare’s tentacles itched to move, twitching minutely underneath him, but he forced them to stay still and lax, the perfect picture of obedience. Horror’s purr kicked up a notch at the sight of him in the nest, right where he  _ belonged. _

Nightmare decided to push it just a bit further, splaying his legs in an invitation that had Horror all but drooling. He knew the other was about two seconds away from jumping his bones, and he couldn’t get enough of the feral look on his face. 

Horror’s heats came less often than anyone else’s, sporadic and unpredictable due to his magic, and they always affected him more than the others. None of them minded playing the game with him, though, even Cross, who had damn near ran away when it’d come out of nowhere, before he’d known about it. He’d seemed all too enthusiastic to participate after it was explained to him, promising Horror a chase of his life right after apologizing for the empty spot in the nest that had Horror whining the whole duration of his heat.

It was an entertaining game, indeed, for everyone involved, and Nightmare would play his part more than happily. He knew just how much it satisfied Horror to have him, their  _ leader, _ submit to him, drinking up the praise and acknowledgement like a monster starving.

“What a magnificent nest,” he said, voice full of wonder as Horror pinned him to it, hot and heavy breaths on his neck, teeth threatening to bite down in the usual spot, right over the claiming bite hidden beneath the layer of dark corruption. He cradled Horror’s skull to his neck, urging him to indulge. “You always make it perfect. Such a perfect mate you are, Horror.”

Nightmare’s words were like pouring gasoline into an inferno, and he welcomed the sting of teeth sinking into his neck just as much as the accompanying, animalistic sound.

Horror’s hands were suddenly everywhere, running down his arms, up and back down his chest, claws digging into his clothes and all but ripping them off the slighter frame. He was diligently lapping up the marrow left in the wake of his biting, even as he pulled the ripped tatters of clothes off of Nightmare and revealed the swirling pool of seafoam magic in his pelvic inlet.

He met Horror’s frustrated growl with a soft chuckle and scratched at the back of his skull, phalanges dragging over the sensitive joints between his neck’s vertebrae. The magic there was heated and crackling with overcharge, something so rare that Nightmare couldn’t help but marvel at it every time.

“Look at you,” he cooed, letting his magic take shape. At the sight of it, Horror growled, the sound appreciative, and one of his hands ran down his ribcage to his stomach, resting there for a moment as their eyes met.

“Gonna… breed ya,” Horror rumbled. His voice was so deep it was barely above a vibration.

“I know you will. Come on, show me what the others are missing. My perfect little mate, always so good to me, aren’t you?”

Nightmare knew exactly what effect his words were having, and he reveled in it, in the way Horror’s eye dilated so much the crimson of it was naught but a thin ring, the way he could spot Horror’s tongue, desperately swallowing down saliva, the way his shorts were tented with a red glow. It was exhilarating, like lying beneath a beast that could tear him to pieces at any moment.

“Come on.  _ Breed me.” _

It took maybe half a second for Horror to have his shorts off and cock buried in his slick cunt, pulling out a groan from the smaller skeleton. The stretch burned in the best of ways, Horror’s cock carving its shape into the seafoam ecto-flesh, turning its outline a dark, mottled purple. His knot teased at Nightmare’s stretched lips, a sting where  _ just  _ a bit of it parted them.

“That’s it,” he praised, slithering a hand down to his own cock. It trailed corruption over the ecto, only to be swatted away and replaced by one of Horror’s own, easily engulfing the whole length in his larger grip. Nightmare chuckled again, though the sound was breathless. “Of course, love. Sorry. Take care of me, won’t you? I’m yours.”

Honestly, he didn’t  _ need  _ to rile the headed monster anymore. Horror’s hips snapped into him in fast, shallow thrusts, never pulling out more than halfway. He panted above Nightmare like a dog, eye screwed shut as he kept a bruising grip on his hip, where there would no doubt be marks left to fuss over later. But Nightmare enjoyed this, enjoyed letting Horror take what he wanted.

What he needed.

And what he needed was apparently to fold Nightmare in half as he leaned over to smash their teeth together in a bruising kiss, tongue shoving its way into his mouth.

Nightmare let him, allowing the heated tongue to ravage his mouth, run along each and every nook and cranny, as if it wanted to replace his taste with Horror's. His legs shook where they bracketed Horror's hips, each thrust making his vision swim with dark spots.

It never took long for Horror's first release; Nightmare suspected it had to do with the praise and rush of claiming his first mate, but he couldn't say for sure. Horror's claws dug into his hip, pace already growing erratic as he teased his knot inside, a little further each time.

The stretch was just as good as his hand on Nightmare's dick, hot and gliding with just enough friction. His entire body shook as the knot popped inside, Horror's frame stilling above him, their teeth separating so Horror could cry out as he spilled himself, a sound not unlike a howl. Nightmare clenched down as he was filled, ecto distending with the sheer amount poured into him, like molten lava.

His own release splattered against Horror's hand and the resulting bulge of his stomach in glowing seafoam, and Nightmare fell lax against the rumpled clothing.

Above him, Horror panted, only to lower himself and nuzzle Nightmare's neck, tongue lapping in broad strokes over the bite he'd re-made, as if in apology. Or maybe to say,  _ 'mine,' _ Nightmare wasn't sure which.

He curled his phalanges around the back of Horror's neck again, stroking in gentle passes over the agitated magic while they waited for Horror's knot to deflate. The overfull feeling was distracting, a pleasant discomfort that had Nightmare wishing to go at least once more. But it was his job this time to take care of them all, and he needed a bit of time to prepare whatever he hadn't managed to before Horror's emotions had gotten too strong.

"You filled me up so nicely," he cooed, pressing a kiss to the top of Horror's skull. His response was a high whine and Horror nuzzling him even closer. With his bulk, he probably could've crushed him, were he not as strong. "Look, not a drop spilled."

He pulled Horror's head away, angling it to look down. The moment his knot started going down, Nightmare slipped a tentacle inside along it, its width replacing it to keep all the rusty magic inside.

Horror purred, only too pleased at the display, and Nightmare chuckled.

"I know, I know. I'll keep it all there, okay? So why don't you go on and bring the rest of our mates here?"

Horror nodded, his pupil a mere slit at the mention. He stood up, towering over Nightmare's slumped form as he looked his handiwork over, gaze lingering on the large pocket of his magic in Nightmare's stomach. It was obvious it took him a lot of willpower to leave him as he was, unattended, but eventually, Horror did grab his axe from where it had been chucked off to the side. His eye glowed, fingers flexing around the handle.

Nightmare licked his teeth.

The Hunt was on.


	2. The white Knight and ebony Pawn

Cross' marrow pounded in his skull, loud and heavy. He'd yelped at the too-loud crackle of a shortcut, too close for comfort, but he took off down the hallway, headed further into the castle. He'd been hanging close by, desperately trying to pretend the sounds from within Horror's room weren't getting to him.

The adrenaline rush certainly helped with the cloud of magic gathering under his clothes. Or maybe just proved to further agitate it, he wasn't sure yet.

Steps resounded behind him, heavy and fast, and he ducked into one of the branching corridors, taking the steps two at a time as he ascended to the next story.

The coast had to be clear so Nightmare wouldn't get caught in the kitchen, so he could bring in the water and food for them. He could remember the extensive explanation of the whole game, as they all sat in the lounge. No one had looked even remotely embarrassed, not even Horror, and yet with every further sentence, Cross had found himself flushing, just the mental image enough to have him uncomfortable under the weight of Killer sprawled across his lap.

It felt silly now, to have been scared.

Horror's growl echoed in the empty hallways, his axe scraping against the wall.

Cross weighed his options, and then skidded to a halt once he came to the end of the winding hallway, ignoring the next staircase. Horror's form was a blurry shadow as he followed, even in the meagre daylight of the moon shining in through the windows.

Cross licked his teeth.

"Hey, big guy," he said, earning himself another growl, low and animalistic. Stars, one wrong move, and he'd be chewed up, wouldn't he? He swallowed, adjusting his stance when the piercing glow of Horror's eye bore into him.

Except he wouldn't.

Horror raised his axe and Cross ran straight at him.

Horror didn't have enough time to adjust, and Cross was smaller than him. He dropped down, sliding across the floorboards straight between Horror's legs, and barely stumbled as he stood back up, taking the same route he'd come from.

"Bye, big guy!" he called behind himself, cursing himself internally right after. As if in retaliation for his stunt, jagged bones rose from the floorboards, some poised to trip him up, some to skewer him where he stood.

There was the distinct sound of a blaster charging behind him.

Cross yelped, almost tripping himself on the stairs. They passed hallway after hallway, and Cross hoped that was enough time for Nightmare to have done his thing. The foyer opened up before them and Cross jumped the railing, another blaster reducing the statue in the upper alcove to nothing more than a pile of rubble.

He slammed the door open, the hinges creaking drowned out by Horror's voice behind him, a snarl that had a shiver running up Cross' spine. He took to the gardens, remembering Dust's command to stay out of the forest. He was a little curious as to what he had planned, but Dust hadn't been keen on sharing. Maybe he would later?

The wind got knocked out of him, a punishment for getting distracted, and Horror was suddenly on him, pinning him to the cobblestone path. Cross writhed under his weight, but it only got him a growl in return, Horror's breath on the back of his neck.

Cross held his breath, SOUL pounding in his ribcage. His mind knew he wasn't in any danger, knew logically that Horror's only desire was to bring him back inside and, as embarrassing as that was to admit, breed him, but his body didn't, tense as a board as adrenaline pumped through him and his fight-or-flight instinct went haywire. Horror's hand circled his neck, putting pressure against his vertebrae; Cross gasped in a breath.

He couldn't believe how exhilarating this felt.

Horror dragged him by his neck backwards, and Cross scrambled along the cobblestones, phalanges digging into the ground as he kicked out, but he couldn't see, and couldn't get a good angle.

From somewhere in the distance echoed a wolf whistle. Both Cross and Horror froze, a low growl coming from Horror as he let go of Cross. He gasped again, falling lax against the ground as he regained his lost breath. He didn't need it, but habits were hard to unlearn, especially in just a couple of minutes.

Horror ran off in the direction the sound had come from, his steps heavy. When Cross raised his head, he caught sight of Killer, all but leading him back into the castle. 

Well, it looked like he had a bit of time to breathe and collect himself. He tried to do so, get his frantic SOULbeat in order, but it was hard. He could still smell Horror, a heavy scent of a forest with each gasped inhale. His magic was going haywire, like a fire in his bones.

He needed a place to hide.

And unfortunately, the best ones would be found inside, so he sneaked his way back in, leaving the front doors open. Just in case he needed to bolt again.

From somewhere above, he could hear footsteps, loud and making the walls shake. A bit of the plaster came loose and showered the carpet before him, and Cross swallowed.

None of the bedrooms would work for a hiding place, not when it'd be so close to Horror's own room. The kitchen might be a good bet; maybe the food would mask his own smell? Only one way to find out, he supposed.

He passed through the empty dining hall, his steps echoing, and he realized he'd never noticed just how large the whole castle was. It seemed only logical, given the fact that it was, indeed, an entire castle, but there was always someone about, making noise, or he'd be out in the middle of the night and too sleepy to notice the vastness. But now, strung up so tight, he noticed every minute shift of the curtains, every little shadow flickering from the wall-mounted torches.

He sped up, just a bit. The sooner he was out of the dining room, the sooner he'd stop thinking about it.

The kitchen was big, with a central island he could imagine servants preparing food on, but it had been remade to give Horror modern equipment, and all of it was spotless. Horror took care of his space.

Cross opened one of the cupboards under the sink and shoved the cleaning supplies out of the way so he could crawl his way into it. It was claustrophobic, and he barely fit, but that wasn't the point of a hiding spot in the first place.

He closed the door, leaving a little crack to peek through. He wasn't sure how long he stayed there, but at some point, the footsteps from afar started getting closer and closer, until he spotted Killer running into the kitchen.

Horror was hot on his trail, his axe leaving a dent in the doorway as he dragged it over the wall. Killer hopped over the kitchen island, and the way he and Horror started circling it would've been funny, if not for the look in Horror's eye, hungry and wild, and his voice, growling loud enough to echo in Cross' skull. They made three full rotations before Horror seemed to lose his patience and raised a wall of bones to cut off Killer's escape route.

"Fuck," Killer muttered, trying to dodge when Horror reached out to grab him, and failing in the most spectacular way imaginable. Horror caught him by the shoulder, slamming him into the bones in a way that had Killer crying out, but more so in shock than any kind of pain. Killer grinned up at him, looking more pleased than he ought to have.

Cross' hands twitched where they were folded up against him, and he debated internally about staying put or leaping out. Killer had saved him before…

Silently, he cursed himself and kicked the cupboard doors open, forcing himself out of the cramped space.

"Horror—"

Horror's head whipped towards him, even as he still held Killer pinned. His crimson eye flashed blue for a second, and the sight was startling enough that Cross didn't have time to react. His SOUL made a sound as it was turned blue, and the next thing he knew, he was slammed into the wall of jagged bones, next to Killer. None of them dug into him, even with the force of his impact, but he struggled to regain his balance nonetheless.

Horror made a sound in the back of his throat, a mix between a purr and a snarl, and looked them both over. His eye almost seemed to glow in the dim light of the kitchen, and the look in it made a shiver run up Cross' spine.

Once Horror got satisfied looking them over, he hoisted Killer up like he weighed nothing at all and threw him over his shoulder. With his free hands, he reached down and grabbed Cross' leg, pulling and knocking the skeleton onto the ground with a resounding thud.

Cross had to angle his head not to bump it against the ground as Horror started dragging them both, down through the dining hall.

"Great job, Crossy," Killer said, having made himself comfortable in his spot, propping his chin up with one arm while the other laid limply over Horror’s shoulder. The sarcasm in his voice was tangible. "Should've stuck to your little hidey hole, I had a plan."

Cross groaned, too preoccupied with keeping his head leaned forwards to grace Killer with his full attention. "How should I know what you've got planned if you didn't tell me?" he grit out. They were in the foyer by then.

"Hey, big guy," Killer said, knocking his skull against the back of Horror's. Horror made another sound, vaguely questioning, and Cross supposed that was the closest to an acknowledgement they'd get with him at this point. "Might wanna lift Crossy up, 'less you want him with a hole in the skull like yours?"

Horror paused, completely stopping in his tracks as they stood at the foot of the stairs. He whined, probably imagining Killer's insinuation, and then, much more gently than he'd been dragging Cross over the floor, he picked him up and threw him over his other shoulder. 

Cross found himself mere inches from Killer and his lopsided grin.

"You're welcome by the way, Crossy," he said, raising a browbone.

"I almost wish I got the concussion. At least then I wouldn't have to listen to you," Cross grumbled right back, but his words lacked any heat.

"Don't forget this is your fault in the first place."

" _ My _ fault how!"

Horror growled, a warning for them to keep it down, but what really shut Cross up was the way his hold on them tightened.

"If you stayed in your little cupboard, you wouldn't've gotten caught. Yet, anyway," Killer said. Cross opted not to make Horror do another one of those growls and simply glared at Killer, hoping it conveyed his exasperation.

From the looks of it, it didn't.

But that didn't matter, because they were already nearing Horror's room, and a mix of apprehension and anticipation swirled in Cross' stomach. Or maybe it was just his magic. It couldn't decide if it wanted to form his body, or an attack.

Horror damn near kicked the door open with a loud grunt. His eye scanned the room, and landed on Nightmare, lounging in the nest like it were his throne, with his tentacles hanging over the edges, contently curling against each other.

He met Horror's gaze and then crooned softly when he noticed the pair of skeletons on his shoulders.

"What a good hunter," he said, and it was  _ Cross _ who shivered. Nightmare's voice was soft and appreciative; he didn't think he'd ever heard this tone from him before. Horror purred and all but preened under the praise, depositing Cross and Killer into the nest none too gently.

Cross landed on someone's jacket, arching to the side to get out of the axe's way as it was pushed aside. The entire nest smelled like all of them, Killer's whittled wood and Dust's ozone and Nightmare's apple pie, but Horror's scent was the strongest, pine in the fall, and blood and fire.

Cross could've gotten lost in it.

But his attention was pulled by Horror above, leaning his head into Nightmare's hand as the guardian stroked it, deft fingers ghosting over the large crack. Horror had started purring and, over his heaving chest, Cross could see the way Nightmare's ecto-stomach was swollen with a pocket of rusty magic. The sight alone made his throat dry and he found his tongue summoned as he swallowed around the dryness.

"You've never brought back two at once," Nightmare drawled, and from the side, Killer scoffed. Nightmare threw him a look, and then grinned. "Every time you exceed my expectations, Horror. Now, why don't you show them their place?"

Horror licked his teeth, eye sliding from Killer to Cross and then back, like he wasn't sure where to look first.

What to indulge in first.

There was a  _ very _ visible strain in his shorts, red glow shining through the fabric, and it made Cross fidget, his own magic begging to form itself. Any and all thoughts of fighting were long gone from his mind.

As Horror looked at them, he started whining, browbones furrowing and hands twitching as he turned to Nightmare, as if for help. Nightmare hummed.

"It's okay," he cooed, sliding up and behind Horror to drape himself over his larger back. His stomach pressed against Horror and made him gasp, the way he could feel Nightmare keeping his promise and  _ not spilling a drop _ oh-so-pleasing. The guardian hooked his chin over Horror's shoulder and offered Killer a grin, edges sharp like razors. "You can't please them both at once, but…"

Cross' eyelights were glued to the tentacle that snaked along the nest and curled around Horror's axe, pulling the weapon close and back towards Horror's hand.

"But it looks like Cross is getting desperate. How about you-" The tentacle pressed the axe into Horror's hand backwards, curling around his wrist instead, to guide the hilt of the weapon towards Killer's spread legs. "-give Killer something to tide him over, until you take care of Cross?"

Nightmare's hum was expectant, and Horror didn't disappoint. Cross barely blinked and the larger skeleton had Killer's shorts yanked down and the handle of his axe pressed to the crimson and soaked lips of his cunt.

"That's it," Nightmare crooned, just as Killer swore, claws digging into the clothes around him and hips arching into the weapon as it was shoved into him.

Cross exhaled in a rush, and that soft sound was enough for Horror to turn to him. His pupil was a mere slit and he grit his teeth in a snarl, one large hand gripping at Cross' hip and turning him over. Warmth rushed up to his skull at the position, his head pushed down to the nest and his hips held aloft by the other.

His magic felt so heated, and he couldn't help but whine when his shorts were pulled down, revealing the swirling pool of it.

Horror leaned over him, breath hot on the back of his skull, and Cross could feel just how hard he was, his cock leading against Cross' coccyx.

"Cross will summon you something nice, won't he?" Nightmare asked, the last part aimed right at Cross, pointed, and he couldn't nod fast enough, letting the magic take shape. It alleviated a bit of the heat in his bones, but replaced it with a new problem instead. Cross buried his head into his arms as he felt slick dripping down his thighs. He was positively  _ soaked, _ and even his cock was dripping precum onto the nest.

Horror's tongue ran along the vertebrae at the back of his neck and he bit down at them with a pleased rumble. A tentacle ghosted over Cross' thigh and made him tense, but it curled into Horror's shirts to pull them down, out of the way.

"Just look how dripping you already got him," Nightmare said, much to Cross' further embarrassment. He was still draped over Horror's back, and entirely too close as Horror kept putting pressure on his neck, lapping away any welling marrow. "Don't be shy, give him what he wants."

Half playing along and half desperate, Cross ground back against Horror's cock, and with a small voice pleaded, "Please, H…"

Horror let go of Cross' neck so he could cry out, a guttural sound as he sunk into his pliant entrance, spreading him with sharp little thrusts.

Cross cried out, turning his head to capture Horror's mouth as he panted right by his acoustic meatus. It was messy and Horror's tongue filled his whole mouth, but at least it muffled the borderline whiny cries as the bigger skeleton kept pushing further and further in, until Cross could feel his knot at his entrance.

It made him clench down, and when Horror started moving, he had to pull away from the kiss to gasp for breath, his entire body buzzing with the pleasure tingling asking his spine.

And the smell was so heavy around him, it felt like it was suffocating him, only further serving to make his magic feel hotter than it was.

Killer whined from the side. Cross couldn't see him, not from this angle, but he could hear Nightmare's chiding tongue click. Killer's whine tapered off into a broken moan.

"Oh, no," Nightmare cooed, "You only get to cum on Horror's cock. Be patient."

Cross shuddered, a moan tearing itself out of him with the way Horror's hips snapped against his. His cock stretched him out so far that he felt like it was reaching up to his throat. His ecto was stretching outwards whenever Horror was fully buried in it, a bulge he was glad was hidden from view under him.

"Fucking shit," Killer muttered, breathless, and Cross could only imagine another one of Nightmare's tentacles curled around the base of his cock to prevent him from coming. He wondered if Nightmare was fucking him with the axe, but he couldn't tell if all the wet, squelching sounds were from him, or Horror fucking him into the nest.

Horror's grip on his hip turned bruising, and his heavy panting moved away as he straightened out, pulling Cross back against his pelvis. It changed the angle and Cross screamed out on the next thrust, Horror's cock reaching the back of his magic even without the knot.

"H-Horror," he moaned, bunching the jacket under him in his fists. He wanted to move, but he couldn't with Horror holding him, and moving him like  _ he _ wanted.

Every time he thrust forward, he pulled Cross back to meet the movement, and Cross couldn't do anything but take it.

"You're doing so well," Nightmare whispered to Horror. Cross didn't need to see it to know he was running his hands over Horror's ribs, the shaky groan was more than enough to paint the picture in his mind. "Why don't you go ahead and give it all to him, hmm? He'd love your knot."

"Please!" Cross cried, feeling the tears welling in his sockets. With every thrust, Horror dragged over his most sensitive spots in the best of ways. "Please, please, please…"

He could hear Killer chuckling at his desperation, but he couldn't find it in himself to react, or even get mad at him, not when Horror growled, his thrusts growing shallow as he forced his knot into his already stretched cunt, a little more with each thrust. Its stretch bordered on a pleasant burn, and Cross squeezed his sockets closed, tears spilling over as his whole body tensed. Horror's knot pushed into him, his length stretching Cross more than he would've thought ecto to be capable of and he wailed into the nest, shaking as the pleasure became too much.

His release splattered the clothes under him in stripes and drenched Horror's lap, and the bigger skeleton fucked him through it, his purr rumbling deep in his ribcage. Cross crumpled down like a house of cards, only held up by the hand on his hip, shaking as his vision swam. His limbs felt leaden, throat raw as he moaned though the pleasure with the aftershocks coursing through his body.

Horror's thrusts stopped abruptly, his cum stretching Cross out even further. His mouth opened in a soundless scream, to complement Horror's loud growl. The sensation of being filled to the brim and past it forced another weak spurt of cum from Cross' tragically untouched cock.

He was sure he blacked out there for a second, because the next thing he was aware of was Horror nuzzling into the back of his neck, his purr still as loud and rumbly as always, and his knot slowly deflating.

Before the cum making his stomach heavy could gush out, something cold forced its way into him, stretching him anew, and Nightmare crooned at Horror, pulling him away.

Horror replied with a pleased noise as Cross all but collapsed into the puddle of slick he'd made under himself, trying to get himself under control.

Killer cried out, his breathing labored, but when Cross tried to turn to look at him, Nightmare's tentacles just came into view, to wipe the tear tracks off his skull.

"It's okay," he said, softly. It took a while to register that he was talking to Cross, and not Horror this time. "You can rest, Horror's got you."

It was tempting, to watch as Horror ravaged Killer too, but the lull of exhaustion and the heavy feeling in his still-summoned ecto was  _ more _ tempting, so he allowed his sockets to drift closed.

Nightmare chuckled, rearranging the guard onto his side to make it more comfortable in him, and then turned his attention onto his other mates.

The axe's handle was completely coated in red slick as he pulled it out, and Killer was twitching minutely, his entrance fluttering around nothing. Every couple of seconds, his grin cracked, teeth parting on soft sighs as the last of Nightmare's tentacles squeezed the base of his cock.

It was a delectable sight, and Horror seemed to think so, too.

Killer splayed his legs as far apart as they'd go. "C'mon, big guy, 'm dying here," he muttered, and that was all it took to have Horror on him, hands gripping his crimson thighs as he replaced the weapon with his cock.

Him and Cross weren't all that different, size-wise at least, and over Horror's shoulder, Nightmare had the perfect view of Horror's cock stretching Killer's stomach with its length. His red was only a little darker than the blood-vivid of Killer's, but not enough for him to be as visible as with the others. But that, in itself, had its appeal.

"He took you so easily," Nightmare taunted, knowing his voice next to Horror's acoustic meatus was getting to him just as much as it was getting to Killer, who rolled his hips.

"'course," he affirmed, with a breathless laugh. "Watchin' you take care of lil Crossy? How - hng - how good y'were to him? Fuck, H, I could cum like this,  _ if _ I could."

Horror growled, his hands visibly trembling where they held Killer's this apart. Nightmare and Killer shared a sly look over his shoulder, and Nightmare pressed himself closer to Horror, his own cock twitching at the added pressure to his stomach.

"What'd you say?" he asked, hands dropped to the other's hips and pushing him forward. The pace Horror set had Killer reaching up to him, clawing at his shoulders. "Should we let him come? So he can do it again as you fill him up?"

Horror growled again, hunching over Killer's slighter form. When he clamped his teeth to Killer's clavicle, his ribcage almost rubbed over the exposed SOUL, and Killer's sockets went wide, leaving tears in the back of Horror's hoodie.

Nightmare huffed in amusement and unwound his tentacle from Killer's cock, bringing it up to his mouth to lick off the slick it'd gathered. Almost instantaneously, Killer jerked, his release crashing over him as he clamped down on Horror, making him grunt.

"Fuck," he mumbled hoarsely, as he let his body be pushed and pulled to the bigger skeleton's whims.

Gently, Nightmare wrapped his free tentacles around Horror's chest and tugged him back, and Killer groaned when the pressure on his SOUL lessened.

The target shape was wavering around the edges, dripping almost as much as his cunt. When he reopened his sockets from where they'd taken shut, there was a faint eyelight in the right one, and Nightmare was more than pleased to see its shape as heart-like as his SOUL was getting to.

"You're such a good mate, Horror," Nightmare said, committing the image under them to memory, as he always did. Killer's salty taste was still on his tongue, clinging to his palate. "Look how much he loves this. Even his SOUL is crying out for you."

Horror's purr kicked up and he nuzzled against the side of Killer's skull. With great effort, he pulled one hand from where it was still gripping Horror's hoodie and stroked over the bigger skeleton's vertebrae, still doing his best to meet the frantic pace.

"Y-yep. Best mate, H. Love ya." Killer's words were punctuated with moans, his voice breaking on some. Nightmare could taste his pleasure in the air, over the heady scent of heat clinging to everything around. "Yer knot, too. Gimme."

The pleasure was getting to the too-much territory, if his usually sharp words were slurring together so much. Even his SOUL had taken on the more usual shape for monsters, beating in time with his ragged breaths.

Horror nodded, almost knocking his skull against Killer's, but the smaller skeleton didn't seem to be complaining.

"Fuck, big guy," his speech devolved fully into gasps and wordless moans, limbs twitching as Horror pounded into him, knot popping inside all at once. Killer cried out, hips arching upwards so sharply his spine nearly bent in two. He came all over himself again while Horror desperately rutted into him even pulling out anymore.

Killer's lips fluttered around the widest part of his knot, fingers twitching as Horror ground out a snarl through grit teeth and came, flooding his insides.

Nightmare found himself mesmerized as he watched the swell of his stomach grow, magic adjusting to accommodate the flood of more of it. He almost looked pregnant, with the minimal difference in their colors, and Nightmare filed the revelation of how appealing he found that thought away for later.

Instead, he muttered quiet praises to Horror as he panted, as they waited for the moment his knot would go down. Diligently, he curled a tentacle into Killer's abused hole, dragging its tip over one of the sensitive spots, if only to hear the sharp gasp turn into a choke of his name.

"They were fools, to run," he repeated his earlier words, though he had no real way of knowing if Horror even remembered them, and pulled himself away from the bigger skeleton's back. "You've pleased them so well, look how happy they are."

Horror rumbled with another purr, looking at both Killer and the sleeping Cross with self-satisfaction and no small amount of love.

"Oh yeah," Killer croaked. He was panting heavily, looking up at them with half-lidded sockets. "So fuckin' happy."

Nightmare leaned himself against the edge of the nest, sighing out softly. His stomach was getting a bit uncomfortable now, unused to holding Horror's load for so long. But his eyelight still sparked with playfulness as he looked up at Horror's kneeling form.

"Just one left. Then you'll have us all in your nest, like it should be."

Horror tensed up with a whine and, as his ecto-flesh dissipated, the wild look in his eye returned. Nightmare handed him his axe, still coated in Killer's drying slick, and he gripped it so right he almost yanked it out of his hold.

He barely pulled his shorts back up before he was rushing out of the room, the door slamming shut behind him. The sound startled Cross awake, and he tried to jump up, but instead just yelped as he gave himself a cramp.

"Wha-"

"Go back to sleep, Cross," Nightmare told him, but Killer stirred next, pushing himself up on wobbly legs, and they both watched, curious. "What are you doing, Killer?"

Killer, in lieu of an answer, stretched his arms above his head and heaved a sigh. The concentration was obvious in the crease of his browbones, but after a moment, he got his body to dissolve, leaving Nightmare's tentacle to curl in on itself as if confused.

"Damn, that's a weird feeling," he muttered, holding a hand to his midriff as if his stomach was still there. "But yeah, I'm heading out again. Since  _ someone _ decided to take away one of Horror's targets." He shot a pointed look at Cross, who only blushed in response.

"Always making my life harder," Nightmare grumbled, leaning back. Horror would most likely take Killer's absence out on him, as the designated nest-keeper. "Make it worth it, will you?"

Killer pulled his shorts back up and shook an arm, dislodging one of the knives hidden in the sleeve to slide into his palm. "Always do."

The guardian could only scoff at he shortcut away, and used his freed tentacle to grab a water bottle from the stash he'd made on the bed.

"Here," he said, handing it over to Cross, who was having trouble sitting up. "If you're not sleeping, might as well stay hydrated."

He took his own advice too, humming as he listened out to the hunger roaming the castle, and the anticipation lurking in the forest. Killer's glee was hiding out in the attic, at least for now. Nightmare downed the entire bottle of water in one go.

He closed his eyesocket.

Nothing to do but wait now.

**Author's Note:**

> The Hunt is indeed on. I hope it's apparent to everyone how consensual and practiced this is. It's a game, and a fun one for everyone. Don't let anything fool you 💜💜


End file.
